Gaming machine artwork

ABSTRACT

A gaming machine artwork assembly includes a carrier on which images to be illuminated are carried. An electroluminescent illuminating arrangement is mounted on an operatively rear surface of the carrier. The electroluminescent illuminating arrangement comprises a plurality of electroluminescent elements, at least one element being associated with each image to be illuminated. A driver circuit is connected to the illuminating arrangement for driving the electroluminescent illuminating arrangement to illuminate selected electroluminescent elements of the arrangement on command from a controller of the gaming machine. The driver circuit includes individual drivers for each electroluminescent element for independently driving the electroluminescent elements and variably controlling the intensity of the illumination of the images with which said electroluminescent elements are associated.

FIELD OF THE INVENTION

This invention relates to a gaming machine. More particularly, theinvention relates to a gaming machine artwork assembly and to a methodof illuminating gaming machine artwork.

BACKGROUND OF THE INVENTION

Presently, to light artwork associated with a game of a gaming machine,it has been necessary to use incandescent lighting or light emittingdiodes (LED's). Incandescent lights have a limited life span and, byusing them, the game can lose its effectiveness by not having theartwork light up as required.

The intensity of incandescent lights or LED's cannot easily be adjustednor adjusted sufficiently rapidly to give a realistic impression of theevents occurring in the game. As a result, when it is necessary tochange lighting intensity or to light up a component or image of theartwork, in response to an event in the game, this cannot be easilyachieved within the required time span.

It will also be appreciated that the artwork comprises numerous imageseach of which may require separate illumination. To effect back lightingof these images by using incandescent lights or LED's, shielding in theform of metal or plastics formwork needs to be applied about each imageto inhibit light leakage. The shielding has to be accurately mounted tomatch the artwork images. Any mismatch or out of tolerance mounting ofthe shielding causes overlapping with other images of the artwork or, inthe case of finer images, lighting the wrong image altogether. Therequirement to make use of shielding has also made it extremelydifficult to light irregular, odd shapes or fine images.

Australian Patent No 741427 (International Publication No WO 99/39552)in the name of Screen Sign Arts Limited entitled “Electroluminescentdisplay” discloses the use of electroluminescent material forillumination purposes. The contents of Australian Patent No 741427 arespecifically incorporated in this specification by reference. Theapplicant proposes use of an electroluminescent illuminatingarrangement.

SUMMARY OF THE INVENTION

According to a first aspect of the invention, there is provided a gamingmachine artwork assembly which includes:

-   -   a carrier on which images to be illuminated are carried;    -   an electroluminescent illuminating arrangement mounted on an        operatively rear surface of the carrier, the electroluminescent        illuminating arrangement comprising a plurality of        electroluminescent elements, at least one element being        associated with each image to be illuminated; and    -   a driver circuit connected to the illuminating arrangement for        driving the electroluminescent illuminating arrangement to        illuminate selected electroluminescent elements of the        arrangement on command from a controller of the gaming machine,        the driver circuit including individual drivers for each        electroluminescent element for independently driving the        electroluminescent elements and variably controlling the        intensity of the illumination of the images with which said        electroluminescent elements are associated.

The carrier may be a planar sheet of material on which the images arecarried. The sheet may be a sheet of plastics material.

Each element of the electroluminescent illuminating arrangement maycomprise, as described in Australian Patent No 741427, a pair ofelectrodes sandwiching a dielectric layer and a phosphor layer, a first,operatively front electrode being mounted to the rear surface of thecarrier. The front electrode may be of a transparent material and,conveniently, may be in the form of an indium tin oxide layer. Thephosphor layer may be carried on a rear surface of the front electrodeand is at least partially encapsulated by the dielectric layer. Asecond, rear electrode may be arranged on top of the dielectric layer toform a structure having a capacitive impedance.

When an alternating voltage is applied across the electrodes, atime-varying electric field is generated in the phosphor layer and thedielectric layer. Electroluminescence occurs in the element by excitingatoms of the phosphor layer by means of the electric field. When theexcitation of the atoms is removed, decay to a ground state of the atomsoccurs via the emission of radiant energy in the visible spectrumresulting in illumination by the electroluminescent element.

As indicated above, the driver circuit may include a driver associatedwith each electroluminescent element.

The driver circuit may include a control device. The control device maybe a dedicated microprocessor executing proprietary software forindividually controlling each driver. The driver associated with eachelectroluminescent element of the artwork may be mapped to a memorylocation of the microprocessor and may be illuminated on command fromthe controller of the gaming machine.

The microprocessor may employ a modulation technique for controlling theintensity of illumination of each electroluminescent element. Themodulation technique employed may be a pulse width modulation (PWM)technique.

The electroluminescent element may be driven by means of an AC signal.Typically, the AC signal has a frequency of about 500 to 1,000 Hz,preferably, about 600 to 900 Hz and, optimally, about 800 Hz.

Each driver may include a zero voltage detector circuit which detects azero crossing of each cycle of the AC signal. For lower intensity, theAC signal may be turned off on the zero crossing for a predeterminednumber of cycles to obtain the required intensity of illumination. Itwill be appreciated that, due to the frequency of the AC signal, even ifthe signal is turned off for a number of cycles, it will be undetectableby the human eye and the likelihood of observing flicker is small.

For maximum intensity, the signal may not be turned off for any numberof cycles. For zero illumination, the signal remains off and, for anintermediate intensity, the signal may be turned off for the appropriatenumber of cycles.

Assuming eight levels of illumination from zero intensity to maximumintensity, seven cycles of the AC signal are used, zero intensity havingno signal. The number of levels could be increased or decreaseddepending on the number of cycles used. The electroluminescent elementsare capacitive in nature, resulting in the AC current signal leading theAC voltage signal by 90°. Therefore, the zero voltage detector maydetect a zero crossing of the voltage signal and, from that, determineor calculate a maximum or peak voltage of the AC voltage signal todetermine the zero crossing of the associated AC current signal. In thecase of half intensity, the driver circuit may, therefore, turn on at amaximum voltage of a first cycle of the AC voltage signal, turn off at amaximum voltage of the fourth cycle and, to commence the next period ofillumination, turn on again at a maximum voltage of the eighth cycle.

The artwork may be arranged in a top box and/or on a belly board of thegaming machine. Additionally, artwork, in accordance with the invention,may be included in tower-like components, known as “traffic lights”, onone or both sides of a monitor of the gaming machine. The “trafficlights” may be mounted on a door of the gaming machine. Due to the lightweight of the artwork of the invention, no major structural alterationsto the door are required.

According to a second aspect of the invention, there is provided amethod of illuminating gaming machine artwork, the method including thesteps of:

-   -   providing a carrier on which images to be illuminated are        carried;    -   illuminating selected images on the carrier on command from a        controller of the gaming machine by means of electroluminescent        elements of an electroluminescent illuminating arrangement        mounted on an operatively rear surface of the carrier; and    -   controlling the intensity of illumination of the        electroluminescent elements to control the intensity of        illumination of the images.

Each electroluminescent element may have a driver associated with it andthe method may include driving each electroluminescent elementindependently via its driver to control the intensity of illumination ofthe image associated with that element independently of each otherimage.

The driver associated with each electroluminescent element of theartwork may include a microprocessor and the method may include mappingto a memory location of the microprocessor the driver associated witheach electroluminescent element of the artwork and illuminating theelectroluminescent element of each selected image on command from thecontroller of the gaming machine.

The method may include using a modulation technique for controlling theintensity of illumination of each electroluminescent element.

Further, the method may include driving each electroluminescent elementby means of an AC signal.

The method may include detecting a zero crossing of each cycle of the ACsignal. For lower intensity illumination, the method may include turningoff the AC signal on the zero crossing for a predetermined number ofcycles to obtain the required intensity of illumination.

The method may include detecting a zero crossing of an AC voltage signaland, from that, determining a peak voltage of the AC voltage signal todetermine the zero crossing of an associated AC current signal.

According to yet a further aspect of the invention, there is provided agaming machine which includes

-   -   a carrier carrying artwork associated with a game of the gaming        machine; and    -   an electroluminescent illuminating arrangement arranged behind        the carrier for illuminating images of the artwork on command        from a controller of the gaming machine.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is now described, by way of example, with reference to theaccompanying diagrammatic drawings in which:

FIG. 1 shows a three dimensional view of a gaming machine, in accordancewith an embodiment of the invention;

FIG. 2 shows a block diagram of a control circuit of the gaming machine;

FIG. 3 shows a schematic, sectional view of a part of artwork of thegaming machine;

FIG. 4 shows a block diagram of control circuitry of the artwork;

FIG. 5 shows a block diagram of a driver circuit of the controlcircuitry;

FIG. 6 shows examples of waveforms of signals in the circuit of FIG. 5;and

FIG. 7 shows a front view of an example of gaming machine artwork, inaccordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

In FIG. 1, reference numeral 10 generally designates a gaming machine inaccordance with an embodiment of the invention. The machine 10 includesa console 12 having a video display unit 14 on which a game 16 isplayed, in use. The game 16 may, for example, be a spinning reel gamewhich simulates the rotation of a number of spinning reels 18. A midtrim20 of the machine 10 houses a bank 22 of buttons for enabling a playerto play the game 16. The midtrim 20 also houses a credit input mechanism24 including a coin input chute 24.1 and a bill collector 24.2.

The machine 10 includes a top box 26 on which artwork 28, in accordancewith an embodiment of the invention, is carried. The artwork 28 includesimages related to the game 18. Further artwork 42, which, desirably, isalso in accordance with an embodiment of the invention, is carried on abelly board 44 of the gaming machine 10.

A coin tray 30 is mounted beneath the console 12 for cash payouts fromthe machine 10.

Referring now to FIG. 2 of the drawings, a control means or controlcircuit 32 is illustrated. A program which implements the game and userinterface is run on a processor 34 of the control circuit 32. Theprocessor 34 forms part of a controller 36 that drives the screen of thevideo display unit 14 and that receives input signals from sensors 38.The sensors 38 include sensors associated with the bank 22 of buttonsand touch sensors mounted in the screen of the video display unit 14.The controller 36 also receives input pulses from the mechanism 24 todetermine whether or not a player has provided sufficient credit tocommence playing. The mechanism 24 may, instead of the coin input chute24.1 or the bill collector 24.2, or in addition thereto, be a creditcard reader (not shown) or any other type of validation device.

Still further, the controller 36 controls illumination of the artwork 28and 42, as will be described in greater detail below.

Finally, the controller 36 drives a payout mechanism 40 which, forexample, may be a coin hopper for feeding coins to the coin tray 30 tomake a pay out to a player when the player wishes to redeem his or hercredit.

Referring to FIG. 4 of the drawings, the artwork 28, 42 is described ingreater detail. The artwork is represented schematically at 50 in FIG. 4of the drawings. As shown in FIG. 3 of the drawings, the artwork 50comprises a front carrier or panel 52 which is transparent. Anelectroluminescent illuminating arrangement 54 is arranged on anoperatively rear surface of the panel 52. It is to be noted that thepanel 52 carries images such as those shown in FIG. 7 of the drawings.

The electroluminescent illuminating arrangement 54 comprises a pluralityof electroluminescent illuminating elements 56. Each image on the panel52 has one or more elements 56 associated with it.

The electroluminescent illuminating arrangement 54 comprises a first,operatively front, transparent electrode 58. The electrode 58 covers therear surface of the carrier 52 and is an indium tin oxide layer.

Each electroluminescent element 56 comprises, in addition, a phosphorlayer 60 in the shape of the image to be illuminated. The layer 60 isapplied to an operatively rear surface of the first electrode 58. Thephosphor layer 60 is encapsulated in a dielectric layer 62. It is to benoted that the dielectric layer 62 overlies the phosphor layer 60 ofeach of the various elements 56 of the electroluminescent illuminatingarrangement 54.

Finally, a second, operatively rear electrode 64 which, once again, isin the shape of the image on the panel 52 to be illuminated is appliedto the dielectric layer 62 in register with its associated phosphorlayer 60. The electrode 64 is of any suitable conductive material, forexample, silver.

It will be appreciated that the electrodes 58 and 64, together with thedielectric layer 62 and phosphor layer 60 sandwiched between them, forma structure having a capacitive impedance. When an alternating electricfield is applied to the electrodes 58 and 64, phosphorescence of thelayer 60 occurs. This occurs as a result of, once the electric field hasbeen removed, atoms in the layer 60 returning to their ground state byreleasing energy which is in the visible spectrum of light.

It is also to be noted that the connection to each of the electrodes 58and 64 have been omitted from FIG. 3 for the sake of clarity. Referenceis made to Australian Patent No. 741427 where the connections aredescribed in greater detail.

The artwork 50 is driven by one or more driver circuits 66 (FIG. 4).Each driver circuit 66, in turn, is controlled by a controller board 68.The controller board 68 receives commands from the game controller 36via a sequencer 70. The controller board 68 receives electrical powerfrom a high voltage power supply 72 which provides an AC signal having afrequency in the range of about 500 to 1000 Hz, preferably about 600 to900 Hz and, optimally, about 800 Hz to the driver circuits 66.

The artwork 28, 42 also includes a plurality of light emitting diodes(LED's) arranged about a periphery of the artwork 28, 42. These LED'sare commonly referred to as chaser LED's 74 which are driven by an LEDdriver 76 from the controller board 68. It is to be noted in FIG. 7 ofthe drawings that part of the image in the top box 26 of the artwork 28is a screen 78. The screen 78 is an LED screen and displays jackpotamounts for a mini, minor, major and grand jackpot associated with theapplicant's game 18, Jackpot Deluxe. The LED's of the screen 78 are alsodriven by the controller board 68.

A further lighting arrangement can be mounted on the gaming machine 10on each side of the video display unit 14. Although not shown in FIG. 1of the drawings, a column of electroluminescent devices, commonlyreferred to as “traffic lights” 79 (FIG. 4), may be mounted on opposedsides of the video display unit 14. The “traffic lights” 79, being ofelectroluminescent construction, are relatively lightweight. As aresult, the “traffic lights” 79 can be mounted on a door of the gamingmachine without significant, if any, structural modification to the doorbeing required. The “traffic lights” 79 are controlled by the controllerboard 68.

Referring now to FIG. 5 of the drawings, a block diagram of part of thecircuitry of the artwork, including the driver circuit 66, is shown.

The driver circuit 66 includes a driver 80 for each electroluminescentelement 56. Each driver 80 is controlled by a control device, in theform of a microprocessor 82, which, in turn, is controlled by thecontroller 36 of the gaming machine 10. The drivers 80 constitute aninterface between low and high voltage circuitry of the artwork 50.

The microprocessor 82 is a dedicated unit executing proprietarysoftware. Individual electroluminescent elements 56 of theelectroluminescent illuminating arrangement 54 are mapped to memorylocations of the microprocessor 82. The appropriate image of the artwork50 is illuminated by energising the relevant electroluminescent elementor elements 56 associated with that image with the required intensity ofillumination as determined by the microprocessor 82 under the control ofthe controller 36.

Each electroluminescent element 56 is supplied with an AC signal. Asindicated above, the AC signal has a frequency of, optimally,approximately 800 Hz.

To effect the required intensity of illumination of the relevant image,the AC signal is modulated by a pulse width modulation (PWM) technique.

The PWM technique employed relies on a zero crossing of cycles of an ACcurrent signal. For this purpose, the driver circuit 66 includes a zerovoltage detector 84. An AC voltage signal is supplied from the AC powersupply 72 to the driver circuit 66 on a line 86. The AC voltage signalfed to the driver circuit 66 on line 86 is shown at 88 in FIG. 6 of thedrawings.

The zero voltage detector 84 detects the zero crossing of the AC voltagesignal 88. From that, the detector 84 determines the position of thepeak of each voltage cycle of the signal 88 using the frequency of thesignal 88. Because the electroluminescent elements 56 are capacitive innature, a current signal, an example of which is shown at 90 in FIG. 6of the drawings, supplied to the artwork 50, leads the voltage signal 88by 90°. Having determined the position of the peak voltage of each cycleof the signal 88, the zero voltage detector 84 is able to determine thezero crossing position of each cycle of the AC current signal 90 as itis in phase with the peak voltage of each cycle of the signal 88.

The processor 82 of the driver circuit 66 issues a control signal 91 asshown in FIG. 6 of the drawings under the control of the controllerboard 68 or sequencer 70, as the case may be. The signal 91 is input toa gate of a triac (not shown) of the relevant driver 80 of the drivercircuit 66 which connects the electroluminescent element 56 associatedwith that driver 80 to ground causing the current signal 90 to besupplied by the driver 80 to the relevant electroluminescent element 56of the artwork 50.

It is assumed that, for full intensity illumination, seven cycles of thesignal 88 are required. The example shown in FIG. 6 of the drawingsillustrates the example of an electroluminescent element 56 beingilluminated at 50% intensity of illumination. The current signal 90 isoutput by the driver 80 to its associated electroluminescent element 56of the artwork 50. Thus, at the input to the driver 80, the signal 91goes high on at a maximum voltage of a first cycle 92 of the signal 88as shown in FIG. 6 of the drawings. The signal 91 goes low at themaximum voltage of the fourth cycle 94 of the signal 88 and, to commencethe next period of illumination, again goes high at the maximum voltageof the eighth cycle 96 of the signal 88 to provide a 50% illumination ofthe artwork 50. As indicated above, while the signal 91 is high, thecurrent signal 90 is applied to the electroluminescent element 56 beingcontrolled.

For various other intensities of illumination, the signal 91 goes lowfor longer or shorter periods of time, as the case may be. It will beappreciated that, due to the relatively high frequency of the currentsignal 90, observable flicker will be minimised. As each element 56 isseparately controlled, it will also be appreciated that each image ofthe artwork 50 can be illuminated with light of the desired intensityindependently of any other image of the artwork 50.

It is to be noted that, to spread the load over different cycles of thepower supply 72, different electroluminescent elements 56 are turned onand off at different cycles of the AC signal 88.

Referring to the specific example shown in FIG. 7 of the drawings, it isto be noted that various images are displayed. Each of these images isindividually illuminated by its own electroluminescent element orelements 56. Thus, for example, a star image as illustrated at 98 isilluminated by its own electroluminescent element 56. A champagne bottle100, which may or may not be illuminated, may give the effect ofchampagne spouting from the bottle 100 in a region 102 of the artwork28, the region 102 being illuminated by one or more electroluminescentelements 56.

Still further, a champagne flute 104, or parts thereof, is/areindividually illuminated as are various other icons such as thoseindicated at 106 associated with jackpot prizes of the applicant's gameJackpot Deluxe™.

It is a particular advantage of the invention that individual elements56 can be illuminated by means of the electroluminescent illuminatingarrangement 54. The artwork 50 can comprise any number of images to beilluminated. For example, for the artwork 28 shown in FIG. 7 of thedrawings, 192 individual images to be illuminated are included in theartwork 28. Each image can be illuminated separately and individuallywith its own intensity under the control of the microprocessor 82 andthe controller 36 of the gaming machine 10 in response to particularactions in the game 16 on the gaming machine 10.

Due to the fact that each electroluminescent element 56 is constitutedby layers, very fine detail can be formed in the images such as thestars 98 shown in the artwork 28 in FIG. 7 of the drawings withoutleakage of light or the need for metal or plastics formwork.

The benefit of switching the signal 88 at a zero crossing also resultsin reduced emissions and makes the design more robust.

The electroluminescent illuminating arrangement 54 is rapidly switchableso that the artwork 28 can be illuminated in real time relative to theevents in the game 16.

It will be appreciated by persons skilled in the art that numerousvariations and/or modifications may be made to the invention as shown inthe specific embodiments without departing from the spirit or scope ofthe invention as broadly described. The present embodiments are,therefore, to be considered in all respects as illustrative and notrestrictive.

1. A gaming machine artwork assembly which includes: a carrier on whichimages to be illuminated are carried; an electroluminescent illuminatingarrangement mounted on an operatively rear surface of the carrier, theelectroluminescent illuminating arrangement comprising a plurality ofelectroluminescent elements, at least one element being associated witheach image to be illuminated; and a driver circuit connected to theilluminating arrangement for driving the electroluminescent illuminatingarrangement to illuminate selected electroluminescent elements of thearrangement on command from a controller of the gaming machine, thedriver circuit including individual drivers for each electroluminescentelement for independently driving the electroluminescent elements andvariably controlling the intensity of the illumination of the imageswith which said electroluminescent elements are associated.
 2. Theassembly of claim 1 in which the carrier is a planar sheet of materialon which the images are carried.
 3. The assembly of claim 1 in whicheach element of the electroluminescent illuminating arrangementcomprises a pair of electrodes sandwiching a dielectric layer and aphosphor layer, a first, operatively front electrode being mounted tothe rear surface of the carrier.
 4. The assembly of claim 3 in which thephosphor layer is carried on a rear surface of the front electrode andis at least partially encapsulated by the dielectric layer.
 5. Theassembly of claim 3 in which a second, operatively rear electrode isarranged on top of the dielectric layer to form a structure having acapacitive impedance.
 6. The assembly claim 1 in which the drivercircuit includes a control device.
 7. The assembly of claim 6 in whichthe control device is a dedicated microprocessor executing proprietarysoftware for individually controlling each driver.
 8. The assembly ofclaim 7 in which the driver associated with each electroluminescentelement of the artwork is mapped to a memory location of themicroprocessor and is illuminated on command from the controller of thegaming machine.
 9. The assembly of claim 7, in which the microprocessoremploys a modulation technique for controlling the intensity ofillumination of each electroluminescent element.
 10. The assembly ofclaim 1 in which the electroluminescent elements are driven by means ofan AC signal.
 11. The assembly of claim 1 in which each driver includesa zero voltage detector circuit which detects a zero crossing of eachcycle of the AC signal.
 12. The assembly of claim 1 in which the artworkis arranged in a top box of the gaming machine.
 13. The assembly ofclaim 1 in which the artwork is arranged on a belly board of the gamingmachine.
 14. The assembly of any one of the preceding claims claim 1 inwhich artwork is included in components on one or both sides of amonitor of the gaming machine.
 15. A method of illuminating gamingmachine artwork, the method including the steps of: providing a carrieron which images to be illuminated are carried; illuminating selectedimages on the carrier on command from a controller of the gaming machineby means of electroluminescent elements of an electroluminescentilluminating arrangement mounted on an operatively rear surface of thecarrier; and controlling the intensity of illumination of theelectroluminescent elements to control the intensity of illumination ofthe images.
 16. The method of claim 15 in which each electroluminescentelement has a driver associated with it and in which the method includesdriving each electroluminescent element independently via its driver tocontrol the intensity of illumination of the image associated with thatelement independently of each other image.
 17. The method of claim 16 inwhich the driver associated with each electroluminescent element of theartwork includes a microprocessor and the method includes mapping to amemory location of the microprocessor the driver associated with eachelectroluminescent element of the artwork and illuminating theelectroluminescent element of each selected image on command from thecontroller of the gaming machine.
 18. The method of claim 15 whichincludes using a modulation technique for controlling the intensity ofillumination of each electroluminescent element.
 19. The method of claim15 which includes driving each electroluminescent element by means of anAC signal.
 20. The method of claim 19 which includes detecting a zerocrossing of each cycle of the AC signal.
 21. The method of claim 20which includes, for lower intensity illumination, turning off the ACsignal on the zero crossing for a predetermined number of cycles toobtain the required intensity of illumination.
 22. The method of claim20 which includes detecting a zero crossing of an AC voltage signal and,from that, determining a peak voltage of the AC voltage signal todetermine the zero crossing of an associated AC current signal.
 23. Agaming machine which includes a carrier carrying artwork associated witha game of the gaming machine; and an electroluminescent illuminatingarrangement arranged behind the carrier for illuminating images of theartwork on command from a controller of the gaming machine.